This invention relates to mechanism for attachment and removal of circular saw blades on both motor driven hand held saws and stationary table saws. Also such mechanism handles other disc tool heads such as grinder wheels, sander discs and buffers.
Blade changes on power circular saws now on the market generally require the use of two tools, one tool to hold the blade, the other tool to unscrew the nut or bolt which holds the blade on the shaft of the saw. One brand of hand saw has a mechanism for locking the drive gears which eliminates the tool for holding the blade. However, they all have at least two or three nuts, bolts and washers which are removed from the shaft in a blade change operation. This is particularly inconvenient in a cluttered workplace, where special tools provided by the saw manufacturer and/or removable parts are often lost. Today, at least ten special purpose saw blades are sold for use in cutting different materials and for different cutting results in the same material. To obtain best results the appropriate cutting blade should be used. When blade changes are difficult, time consuming, or when special tools are misplaced, blade changes are postponed or not done at all. Therefore there is a need for having a mechanism which is used to more quickly attach and remove circular saw blades, etc. and which is retrofitted to existing hand held power saws and table saws.